1. Neuroscience  Parts of a neuron  Action potential  Major neurotransmitters  Agonists/Antagonists

2. Neural and Hormonal Systems Neurons are to the nervous system as hormones are to the endocrine system Nervous System- fast response and quick to leave Endocrine System-slower response and stay in your body longer

3. History of the Mind In 1800, Franz Gall suggested, that bumps of the skull represented mental abilities. His theory though incorrect, nevertheless proposed different mental abilities were modular. Phrenology Bettman/ Corbis

4. Neural Communication The body’s information system is built from billions of interconnected cells called neurons.

5. Neural Communication Note similarity of brain regions involved with information processing of similar kind. Neurobiologists and other investigators understand that information processing in humans and animals operate similarly.

6. Neuron A nerve cell or a neuron consists of many different parts.

7. Parts of a Neuron Cell Body: Life support center of the neuron. Dendrites: Branching extensions at the cell body. Receives messages from other neurons. Axon: Long single extension of a neuron, covered with myelin sheath to insulate and speed up messages through neurons. Terminals of axon (terminal buttons): Branched ending of axons. Transmit neurotransmiters to other neurons.

8. Action Potential A neural impulse. A brief electrical charge that travels down an axon generated by the movement of positively charged atoms in and out of channels in the axon’s membrane.

9. Depolarization & Hyperpolarization Depolarization: Depolarization occurs, when positive ions enter the neuron, making it more susceptible to fire an action potential. When negative ions enter the neuron making it less susceptible to fire, hyperpolarization occurs.

10. Threshold Threshold: Each neuron receives depolarizing and hyperpolarizing currents from many neurons. When the depolarizing current (positive ions) minus the hyperpolarizing current (negative ions) exceed minimum intensity (threshold) the neuron fires an action potential.

11. Refractory Period & Pumps Refractory Period: After a neuron has fired an action potential it pauses for a short period to recharge itself to fire again. Sodium-Potassium Pumps: Sodium-potassium pumps pump positive ions out from the inside of the neuron, making them ready for another action potential.

12. Action Potential Properties All-or-None Response: When depolarizing current exceeds the threshold a neuron will fire, and below threshold it will not. Intensity of an action potential remains the same, throughout the length of the axon.

13. Synapse Synapse [SIN-aps] a junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. This tiny gap is called the synaptic gap or cleft.

14. Neurotransmitters Neurotransmitters (chemicals) released from the sending neuron, travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing it to generate an action potential. May be “excitatory” or “inhibitory”

15. Reuptake Neurotransmitters in the synapse are reabsorbed into the sending neurons through the process of reuptake. Don’t move on to the next neuron. For example: People who suffer from depression have lower levels of serotonin. They may take an SSRI which blocks reuptake (thus flooding the synapse with more serotonin)

16. How Neurotransmitters Influence Us Serotonin pathways are involved with mood regulation (depression). From Mapping the Mind, Rita Carter, © 1989 University of California Press

17. Dopamine Pathways Dopamine pathways are involved with diseases like schizophrenia and Parkinson’s disease. From Mapping the Mind, Rita Carter, © 1989 University of California Press

18. Neurotransmitters

19. Lock & Key Mechanism Neurotransmitters bind to the receptors of the receiving neuron in a key-lock mechanism.

20. Agonists

21. Antagonists

22. Nervous System  Nervous system  Afferent/Efferent neurons  Parts of the autonomic nervous system  Endocrine system

23. Nervous System Central Nervous System (CNS) Peripheral Nervous System (PNS)

24. The Nervous System Nervous System: Consists of all the nerve cells. It is the body’s speedy, electrochemical communication system. Central Nervous System (CNS): the brain and spinal cord. Peripheral Nervous System (PNS): the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

25. The Nervous System

26. Kinds of Neurons Sensory Neurons (afferent) carry incoming information from the sense receptors to the CNS. Motor Neurons (efferent) carry outgoing information from the CNS to muscles and glands. Interneurons connect the two neurons. Sensory Neuron (Bipolar) Interneuron Neuron (Unipolar) Motor Neuron (Multipolar)

27. Kinds of Glial Cells Glial cells function as support cells, hold together message sending neurons and support their functioning. Kind of like “glue” Example: Schwann cells insulate neurons as myelin.

28. Peripheral Nervous System Somatic Nervous System: The division of the peripheral nervous system that controls the body’s skeletal muscles. You have “some” control of this. Autonomic Nervous System: Part of the PNS that controls the glands and other muscles. Functions automatically.

29. The Nerves Nerves consist of neural “cables” containing many axons. They are part of the peripheral nervous system, and connect muscles, glands, and sense organs to the central nervous system.

30. Autonomic Nervous System (ANS) Sympathetic Nervous System: division of the ANS that arouses the body, mobilizing its energy in stressful situations. Gets you ready for fight or flight. Parasympathetic Nervous System: division of the ANS that calms the body, conserving its energy. Brings you back down after the threat is over.

31. Autonomic Nervous System (ANS) Sympathetic NS “Arouses” (fight-or-flight) Parasympathetic NS “Calms” (rest and digest)

32. The Endocrine System Endocrine System is the body’s “slow” chemical communication system. Communication is carried out by hormones synthesized by a set of glands.

33. Hormones Hormones are chemicals synthesized by the endocrine glands and secreted in the bloodstream. Hormones affect the brain and many other tissues of the body. Hormones remain in your system longer than neurotransmitters. For example, epinephrine (adrenaline) increases heart rate, blood pressure, blood sugar and feelings of excitement during emergency situations. After the situation has passed, you may continue to tremble.

34. Pituitary Gland Is called the “master gland.” Anterior pituitary lobe releases hormones that regulate other glands. Posterior lobe regulates water and salt balance.

35. Pineal gland Located near the center of the brain between the two hemispheres, shaped like a pine cone Secretes the hormone melatonin which influences our sleep/wake cycle Connects the endocrine system with the nervous system (allows them to communicate)

36. Thyroid & Parathyroid Glands Regulate metabolic and calcium rate.

37. Adrenal Glands and Pancreas Adrenal glands consists of adrenal medulla and cortex. Medulla secretes hormones (epinephrine and norepinephrine) during stress and emotions, and adrenal cortex regulates salt and carbohydrate metabolism. The pancreas regulates the level of sugar in the blood by producing insulin. It also plays a role in the digestive system

38. Gonads Sex glands are differentially placed in men and women. Regulate bodily development and maintain reproductive organs in adults.

39. AP Test info… Know the order of an action potential fire Afferent (sensory) vs Efferent (motor) neurons Sympathetic vs parasympathetic Destruction of the myelin sheath causes… Low AcH causes…

40. Neuron Review What are the 3 main structures of all Neurons? What does myelin do? What is the impact of alcohol on the brain? Ecstasy? How are axons and Dendrites different? In educated people neurons are… Afferent neurons (sensory)– Send information from the body to the brain Efferent neurons (motor)– Send information from the brain to the body.

41. Neurotransmitter Review Low levels of this neurotransmitter may result in depression and suicide. Serotonin Excess amounts of this neurotransmitter may result in Schizophrenia Dopamine Due to it also being a hormone, this neurotransmitter is also known as noradrenaline. Norepinephrine Low levels of this neurotransmitter may be responsible for Alzheimer’s Disease. Acetylcholine (Ach)

42. Neurotransmitter Review Low levels of this neurotransmitter leads to Parkinson’s disease. High levels??? Dopamine This neurotransmitter is used during muscle contraction. Acetylcholine What is the major inhibitory neurotransmitter? GABA Lower levels of this neurotransmitter are generally found in women. Serotonin